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Bouncing of Hydroxylated Silica Nanoparticles: an Atomistic Study Based on REAX Potentials.

ABSTRACT: Clean silica surfaces have a high surface energy. In consequence, colliding silica nanoparticles will stick rather than bounce over a wide range of collision velocities. Often, however, silica surfaces are passivated by adsorbates, in particular water, which considerably reduce the surface energy. We study the effect of surface hydroxylation on silica nanoparticle collisions by atomistic simulation, using the REAX potential that allows for bond breaking and formation. We find that the bouncing velocity is reduced by more than an order of magnitude compared to clean nanoparticle collisions.

SUBMITTER: Nietiadi ML

PROVIDER: S-EPMC7105590 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Bouncing of Hydroxylated Silica Nanoparticles: an Atomistic Study Based on REAX Potentials.

Nietiadi Maureen L ML Rosandi Yudi Y Urbassek Herbert M HM

Nanoscale research letters 20200330 1

Clean silica surfaces have a high surface energy. In consequence, colliding silica nanoparticles will stick rather than bounce over a wide range of collision velocities. Often, however, silica surfaces are passivated by adsorbates, in particular water, which considerably reduce the surface energy. We study the effect of surface hydroxylation on silica nanoparticle collisions by atomistic simulation, using the REAX potential that allows for bond breaking and formation. We find that the bouncing v ...[more]

PMID: 32232683

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